The invention relates generally to the fields of electromyographic monitoring and biofeedback, and more specifically to biofeedback devices and techniques for treating bruxism.
Bruxism has generally been defined as the nonfunctional clenching, grinding, gritting, gnashing, and/or clicking of the teeth. Bruxism can occur while a person is awake or asleep. When the phenomenon occurs during sleep, it is called nocturnal bruxism. Even when it occurs during waking hours, the bruxer is often not conscious of the activity. Biting force exerted during bruxism often significantly exceeds peak biting force exerted during normal chewing. Biting forces exceeding 700 pounds have been measured during bruxing events. Chronic bruxism may result in musculoskeletal pain, headaches, and damage to the teeth and/or the temporomandibular joint.
The primary treatment for nocturnal bruxism is the use of intra-oral occlusal splints or "mouth guards," which are generally semi-rigid plastic covers for the upper or lower teeth. Occlusal splints are generally fabricated for a specific individual from an impression taken of the individual's teeth. While some studies have shown that the wearing of an occlusal splint may reduce bruxing event duration and intensity, the large replacement market for "chewed up" occlusal splints attests to the role of the splint primarily to protect teeth from damage, rather than as a cure for bruxism. Even as a symptomatic treatment, occlusal splints often only protect the teeth themselves, while the user may still suffer musculoskeletal pain and possible damage to the temporomandibular joint.
Occlusal splints present numerous inconveniences to the user. They require frequent cleaning, they are difficult to clean, they require periodic replacement, they inhibit speech, and they are frequently lost. For couples sleeping together, occlusal splints are far from "romantic." Some users perceive that occlusal splints accelerate tooth decay.
Dental researchers and clinicians have made several attempts to address the underlying causes of bruxism through biofeedback. Most commonly, an electromyograph was used to sense the action of the masseter muscle. When muscle activity was detected, an audible tone was generated. This tone alerted the individual that he or she was bruxing. The intention of this biofeedback approach was that a relatively short period of treatment would result in the long-term elimination of the bruxing behavior. Most of the shorter studies indicated that bruxism resumed once the treatment was discontinued. One longer study offered some evidence of sustained reduction in bruxism with longer term use and decreasing frequency of use of the biofeedback apparatus. Because these previous attempts to use biofeedback devices involved bulky electronics and required electrodes to be attached adhesively to the face, they were impractical for long-term use in treating bruxism, and not well suited for consumer use.
Some variations on this biofeedback approach known in the art incorporate sensing means into an occlusal splint in order to sense the onset of bruxing. These approaches require the presence of electrical devices in the mouth, including, in many cases, batteries, which may contain highly toxic substances. The electrical and chemical health risks of these devices add to the general drawbacks of intra-oral splints described above. In addition, many of these attempts have resulted in bulky devices which would be even more uncomfortable for the user than traditional occlusal splints.
It is the object of this invention to provide a convenient, comfortable, reliable, effective, economical, aesthetically pleasing means of providing long-term biofeedback to treat bruxism. It is a further objective of this invention to provide a bruxism treatment means which does not interfere with normal daily activities. It is a further object of this invention to avoid the presence of occlusal splints or other foreign objects in the mouth of the user. It is a further object of the invention to avoid the adhesive attachment of electrodes to the skin of the user. It is a further object of this invention to provide a user-friendly means for clinicians and bruxers to gather comprehensive data on the occurrence of bruxing events including time, duration, and intensity data. It is a further objective of this invention to provide a means for treatment of bruxism (or gathering of data on bruxism) which is wearable as an attractive, unobtrusive, comfortable article of clothing, which does not interfere with normal activities. It is a further object of this invention to provide a reliable, robust bio-feedback mechanism which is readily perceived by the user while remaining relatively unnoticable to persons in the user's immediate surroundings.